Changes in Biomarkers of Redox Status in Saliva of Pigs after an Experimental Sepsis Induction

Abstract

Saliva from pigs is gaining attention as an easy sample to obtain, being a source of biomarkers that can provide information on animal health and welfare. This study aimed to evaluate the changes that can occur in salivary biomarkers of the redox status of pigs with an experimentally induced sepsis. For that, the cupric reducing antioxidant capacity (CUPRAC), ferric reducing ability of saliva (FRAS), Trolox equivalent antioxidant capacity (TEAC), advanced oxidation protein products (AOPP), ferrous oxidation-xylenol orange (FOX), peroxide activity (POX-Act), and reactive oxygen-derived compounds (d-ROMs) were measured in the saliva of pigs with experimentally induced sepsis by endotoxin lipopolysaccharide (LPS), non-septic inflammation induced by turpentine, and in healthy individuals before and after 3 h, 6 h, 24 h, and 48 h. AOPP, POX-Act, and d-ROMs in the sepsis group were higher than in the control from 3 h to 24 h after the inoculation. CUPRAC, FRAS, and TEAC were higher in sepsis than the control group at 24 h. These changes were of higher magnitude than those that occurred in the turpentine group. In conclusion, our findings reveal that sepsis produces changes in salivary biomarkers of redox status, which opens the possibility of using them as potential biomarkers in this species.

Keywords: antioxidants; cupric; ferric; inflammation; oxidative stress; peroxides.

Figure 1

(a) Cupric reducing antioxidant capacity (CUPRAC), (b) ferric reducing ability of saliva (FRAS), (c) Trolox equivalent antioxidant capacity (TEAC), and (d) uric acid concentrations in control (▲), lipopolysaccharide (LPS)-treated pigs (●), and turpentine (TURP)-treated pigs (■) before (basal) and after 3 h, 6 h, 24 h, and 48 h the inoculations. The results are presented as median with an interquartile range. #, significantly different from the control group (p < 0.05; one-way ANOVA with Sidak’s multiple comparisons test). Differences between times are indicated by bars and the obtained p-value (one-way ANOVA with Tukey’s multiple comparison test).

Figure 2

Salivary (a) advanced oxidation protein products (AOPP), (b) ferrous oxidation-xylenol orange (FOX), (c) peroxide activity (POX-Act), and (d) reactive-oxygen-derived compounds (d-ROMs) concentrations in control (▲), lipopolysaccharide (LPS)-treated pigs (●), and turpentine (TURP)-treated pigs (■) before (basal) and after 3 h, 6 h, 24 h, and 48 h the inoculations. The results are presented as median with an interquartile range. #, significantly different from the control group; *, significantly different from TURP-treated pigs (p < 0.05; one-way ANOVA with Sidak’s multiple comparisons test). Differences between times are indicated by bars and the obtained p-value (one-way ANOVA with Tukey’s multiple comparison test).